Ankle sprains are injuries to the ligaments typically on the outside of the ankle joint; usually brought on by twisting of the ankle.
The ankle ligaments usually involved in an ankle sprain are also known as the lateral collateral ligaments which help to stabilize the ankle mortise. The lateral collateral ligaments of the ankle are comprised of the anterior talofibular ligament, the calcaneofibular ligament and the posterior talofibular ligament.
Function of the Lateral (outside) Ankle Ligaments
The lateral collateral ligaments provide stability to the ankle throughout the gait cycle as the foot bends up and down. Therefore, total lateral stability of the ankle is provided by these three ligaments. Rolling in of the foot (inversion), with the sole of the foot towards the opposite leg, is defined as a lateral ankle sprain and can injure the ligaments.
The most anterior (front) and most frequently injured of these ligaments is the anterior talofibular ligament. This ligament is intracapsular, which means it is contiguous with the lining of the ankle capsule.
The main function of the anterior talofibular ligament is the prevention of axial or rotational instability of the ankle. Along with the calcaneofibular ligament (CFL) and posterior talofibular ligament, the ATF prevents inversion or rolling in of the foot. Irregularity of the ground, or laterally directed force, can cause the foot to twist.
Recurrent injuries to the lateral ankle ligaments can cause long standing or chronic injuries to the lateral ankle ligaments. This chronic ankle instability means that the lateral ankle ligaments no longer provide the ability to stop ankle twisting and to hold the Talus within the ankle joint. As you walk or run with an unstable ankle, the talus can twist within the joint. This abnormal movement redirects force to the outside of the joint which causes the foot to roll to the inside producing further tearing of the ligament and further injury.
Conservative treatment for this condition usually begins with RICE (rest, ice, compression elevation) is the standard initial treatment. Allowing the ligaments to heal in the correct position and at the correct length depends on how quickly treatment is initiated and severity of injury.
Surgical treatment of the ankle ligaments are performed when instability develops and the condition can no longer be treated by conservative means. Sometimes this involves imbrication (overlapping) of the injured ligaments or reconstruction with the help of the tendons of the lateral ankle (peroneal tendons).